/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.facebook.presto.execution.scheduler;

import com.facebook.presto.Session;

import java.util.Collection;

import static com.facebook.presto.SystemSessionProperties.getMaxStageCountForEagerScheduling;

public class AdaptivePhasedExecutionPolicy
        implements ExecutionPolicy
{
    @Override
    public ExecutionSchedule createExecutionSchedule(Session session, Collection<StageExecutionAndScheduler> stages)
    {
        if (stages.size() > getMaxStageCountForEagerScheduling(session)) {
            return new PhasedExecutionSchedule(stages);
        }
        else {
            return new AllAtOnceExecutionSchedule(stages);
        }
    }
}
